Preparation of Ag_2S-coatecJ ZnS particles by an ion exchange method -effect of reaction conditions on the morphology of coated particles

摘要

In the preparation of multicomponent materials, the use of a raw mixture in which all components are uniformly dispersed is essential to obtain materials with finely controlled microstructure. When the amount of component to be mixed is small, uniform mixing is especially important, but is difficult using conventional mechanical mixing. To prepare a uniform raw mixture, the preparation of composite particles by a method in which one component is coated with another component has attracted increasing attention. There are two typical methods for the preparation of composite particles with a layer-coated structure. One is the controlled deposition of second phase on suspended core particles from solution or CVD systems [1-4]. The other is a cation exchange method in liquid phase. In the latter, cations in the surface layer of core particles are exchanged with cations in solution, resulting in the formation of a new insoluble layer on the core particles [5].